The present invention is related to a fluid flow sensing device, particularly to the type having a ring member to sense the fluid flow and to actuate a metallic sensing means, so as to control a compressor.
A prior art fluid flow sensor 1 shown in FIG. 1 has a spring 2 to laterally bias a level 4 extending from the sensor 1, and a probe 3 connected to the level 4. While the fluid flows in a tube as indicated by an arrow shown in dashed line, it forces the probe to activate the fluid flow sensor, so as to control a compressor.
However, it is observed that the components of the prior art device are relatively complicated and particularly, not suitable for installation in a small diameter tube. Moreover, since the spring and level are exposed to the fluid, corrosion of the elements is common.